The objective of this work was to demonstrate the relationship among the anteroposterior diameter of the high aerial vias and the esqueletical class. This was a quantitative research; the design was transversal correlations. The population was of 40 patients. The tool used to identify the esqueletical class accordingly with the Steiner and Wits cefalograrrts was a card for the analysis of the esqueletical class validated by expert judgment. The tool u sed to identify the anteroposterior diameter of the high aerial vias was a card for the analysis ofthe high aerial vias validated by expert judgment. The general mean of the anteroposterior diameter of the superior aerial vias was 9. 75 which is considered to be narrow. The general mean ofthe anteroposterior diameter of the inferior high aerial vias was 12.48 which is considered to be wide. The esqueletical classification using the Steiner method show that 60 % of the patients presented esqueletical class I, 32.5 % presented esqueletical class II, and the remaining, 7.5 %, was esqueletical class III. The esqueletical classification using the Wits method shown that 27.5% ofthe patients presented esqueletical class I 17.5% presented esqueletical class II, and the remaining, 55.0 %, was esqueletical class III. The esqueletical pattern among the Steiner and With methods are statistically different. There was not a relationship among the anteroposterior diameter of the superior pharynx and the esqueletical class accordingly with Steiner (Chi = 0.648, degrees of freedom = 2, and p value = 0.710). There was not relationship among the anteroposterior diameter of the inferior pharynx and the esqueletical class accordingly to Steiner (Chi O 5.504, degrees offreedom = 2, and p value = 0.064).